#!/bin/python

import sys

def printShortestPath(n, i_start, j_start, i_end, j_end):
    if abs(i_start-i_end)%2!=0:
        print "Impossible"
        
    else:
        cnt=0
        stri=""
        if i_start<i_end:
            if j_start<j_end:
                for i in range(abs(i_end-i_start)/2):
                    stri+="LR "
                    cnt+=1
                    j_start+=1
            elif j_start>j_end:
                for i in range(abs(i_start-i_end)/2):
                    stri+="UR "
                    cnt+=1
                    j_start+=1
                
            for i in range(abs(j_end-j_start)/2):
                cnt+=1
                stri+="R "
            if j_start==j_end:
                for i in range((i_start-i_end)/2):
                    cnt+=1
                    stri+="L "
                for i in range((i_start-i_end)/2):
                    cnt+=1
                    stri+="LR "
                    
                    
        elif i_start>i_end:
            if j_start<j_end:
                for i in range(abs(i_end-i_start)/2):
                    stri+="LL "
                    cnt+=1
                    j_start-=1
            elif j_start>j_end:
                for i in range(abs(i_start-i_end)/2):
                    stri+="UL "
                    cnt+=1
                    j_start-=1
                
            for i in range(abs(j_end-j_start)/2):
                cnt+=1
                stri+="L "
            if j_start==j_end:
                for i in range((i_start-i_end)/2):
                    cnt+=1
                    stri+="L "
                for i in range((i_start-i_end)/2):
                    cnt+=1
                    stri+="UR "
            
            
        print cnt
        print stri
        
            
           
    #  Print the distance along with the sequence of moves.

if __name__ == "__main__":
    n = int(raw_input().strip())
    i_start, j_start, i_end, j_end = raw_input().strip().split(' ')
    i_start, j_start, i_end, j_end = [int(i_start), int(j_start), int(i_end), int(j_end)]
    printShortestPath(n, i_start, j_start, i_end, j_end)